Differential diagnosis of a tender goiter.

Subacute thyroiditis is generally felt to have a viral etiology, and the diagnosis is usually obvious when the patient presents with a diffusely enlarged and very tender thyroid gland associated with elevated free T4 levels, elevated sedimentation rate, low radioiodine uptake and/or nonvisualization on scan and often some systemic symptoms. Subacute thyroiditis can be unilateral or focal (1,2). Corticosteroids are very effective in relieving symptoms of subacute thyroiditis, often within 24 hr (3). Three patients are presented where the initial impression was subacute thyroiditis, there was a clinical response to prednisone, but none of the patients actually had subacute thyroiditis.